Buggy code:
public ContextManager getContextManager ( ) { } public void setDebug ( int debug ) { } boolean noClassLoaders = false ; public void setNoClassloaders ( boolean b ) { } public void setHome ( String s ) { } public void setInstall ( String install ) { } public void setConfig ( String s ) { } public void setSandbox ( boolean b ) { } public void setJkconf ( boolean b ) { } public void setStart ( boolean b ) { } public void setEstart ( boolean b ) { } public void setRun ( boolean b ) { } public void setHelp ( boolean b ) { } public void setProperty ( String name , String v ) { } public void setAttribute ( String name , Object v ) { } public void addProperty ( Property prop ) { } public void setApplication ( Object app ) { } public Object getApplication ( ) { } Vector modules = new Vector ( ) ; public int addModule ( BaseInterceptor ri ) throws TomcatException { } public int addModule ( String className ) throws TomcatException { } public int findModule ( String className , int startPos ) { } public void setModuleProperty ( int id , String name , String value ) throws TomcatException { } public void addServerXmlModules ( ) throws TomcatException { } public void addDefaultModules ( ) throws TomcatException { } public void addAutoDeploy ( ) throws TomcatException { } protected boolean initialized = false ; public Context addContext ( String ctxPath , URL docRoot , String [ ] hosts ) throws TomcatException { } public Context getContext ( String host , String cpath ) { } public void initContextManager ( ) throws TomcatException { } public void start ( ) throws TomcatException { } public void shutdown ( ) throws TomcatException { } public void stop ( ) throws TomcatException { } public int addEndpoint ( int port , InetAddress addr , String hostname ) throws TomcatException { } public int addAjpEndpoint ( int port , InetAddress addr , String hostname ) throws TomcatException { } public int addSecureEndpoint ( int port , InetAddress addr , String hostname , String keyFile , String keyPass ) throws TomcatException { } public void addDefaultConnectors ( ) throws TomcatException { } public void execute ( ) throws Exception { } public void execute1 ( ) throws Exception { } protected String [ ] args = null ; public void setArgs ( String [ ] args ) { } public boolean processArgs ( String [ ] args ) { } public static void main ( String [ ] args ) { } public void cleanupPrevious ( ) { } private void setTomcatProperties ( ) throws TomcatException { } ClassLoader parentCL ; ClassLoader appsCL ; ClassLoader commonCL ; ClassLoader containerCL ; ClassLoader modulesCL ; URL [ ] commonCP ; URL [ ] modulesCP ; URL [ ] appsCP ; URL [ ] containerCP ; public void setParentClassLoader ( ClassLoader cl ) { } public void setCommonClassLoader ( ClassLoader cl ) { } public void setCommonClassPath ( URL [ ] cp ) { } public void setAppsClassLoader ( ClassLoader cl ) { } public void setContainerClassLoader ( ClassLoader cl ) { } public ClassLoader getContainerClassLoader ( ) { } static final Jdk11Compat jdk11Compat = Jdk11Compat . getJdkCompat ( ) ; public static final String PROPERTY_APPS_LOADER = "org.apache.tomcat.apps.classpath" ; public static final String PROPERTY_CONTAINER_LOADER = "org.apache.tomcat.container.classpath" ; public void initClassLoaders ( ) throws IOException , MalformedURLException { if ( ( dL ) > 0 ) debug ( ( "Init<seq2seq4repair_space>class<seq2seq4repair_space>loaders<seq2seq4repair_space>" + ( noClassLoaders ) ) ) ; if ( noClassLoaders ) { commonCL = this . getClass ( ) . getClassLoader ( ) ; if ( ( commonCL ) == null ) { <START_BUG> commonCL = new URLClassLoader ( new URL [ ] { } , null ) ; <END_BUG> } parentCL = commonCL ; containerCL = commonCL ; modulesCL = commonCL ; if ( ( dL ) > 0 ) debug ( ( "All<seq2seq4repair_space>class<seq2seq4repair_space>loaders<seq2seq4repair_space>" + ( commonCL ) ) ) ; contextM . setParentLoader ( parentCL ) ; contextM . setCommonLoader ( modulesCL ) ; contextM . setContainerLoader ( containerCL ) ; contextM . setAppsLoader ( appsCL ) ; return ; } if ( ( parentCL ) == null ) { if ( ( dL ) > 0 ) debug ( "Default<seq2seq4repair_space>parent<seq2seq4repair_space>loader:<seq2seq4repair_space>null" ) ; } String prefix = ( ( ( installDir ) + ( File . separator ) ) + "lib" ) + ( File . separator ) ; if ( ( commonCL ) == null ) { debug ( "Default<seq2seq4repair_space>commonCL<seq2seq4repair_space>" ) ; commonCL = this . getClass ( ) . getClassLoader ( ) ; } modulesCP = getModulesCommonCP ( ) ; if ( ( modulesCP ) == null ) { modulesCL = commonCL ; } else { if ( ( dL ) > 0 ) IntrospectionUtils . displayClassPath ( "Modules-common" , modulesCP ) ; modulesCL = EmbededTomcat . jdk11Compat . newClassLoaderInstance ( modulesCP , commonCL ) ; } if ( ( containerCL ) == null ) { if ( ( dL ) > 0 ) debug ( ( ( ( ( "Dir<seq2seq4repair_space>:<seq2seq4repair_space>" + prefix ) + "container" ) + "<seq2seq4repair_space>" ) + ( EmbededTomcat . PROPERTY_CONTAINER_LOADER ) ) ) ; containerCP = IntrospectionUtils . getClassPath ( ( prefix + "container" ) , null , EmbededTomcat . PROPERTY_CONTAINER_LOADER , true ) ; containerCP = addModulesContainerCP ( containerCP ) ; containerCL = EmbededTomcat . jdk11Compat . newClassLoaderInstance ( containerCP , modulesCL ) ; if ( ( dL ) > 0 ) IntrospectionUtils . displayClassPath ( "ContainerCP" , containerCP ) ; } if ( ( appsCL ) == null ) { appsCP = IntrospectionUtils . getClassPath ( ( prefix + "apps" ) , null , EmbededTomcat . PROPERTY_APPS_LOADER , false ) ; appsCL = EmbededTomcat . jdk11Compat . newClassLoaderInstance ( appsCP , modulesCL ) ; } String cp = System . getProperty ( "tc_path_add" ) ;

Fix:
commonCL = EmbededTomcat . jdk11Compat . newClassLoaderInstance ( new URL [ ] { } , null ) ;